Teledyne T3DSO1000, User Manual, Page: 76 / 227

58 User Manual
Note: adjust the time scale and horizontal position will not affect the holdoff time.
Trigger Holdoff
Trigger holdoff can be used to stabilize the trigger on complex waveforms (such as pulse
streams or burst waveforms). Holdoff by time is the amount of time that the oscilloscope
waits before re-arming the trigger circuitry. The oscilloscope will not trigger until the holdoff
time expires.
Use the holdoff to trigger on repetitive waveforms that have multiple edges (or other
events) between waveform repetitions. You can also use holdoff to trigger on the first
edge of a burst when you know the minimum time between bursts.
For example, to get a stable trigger on the repetitive pulse burst shown below, set the
holdoff time to be >200 ns but <600 ns.
Holdoff
200ns 600ns
Trigger Point
The correct holdoff setting is typically slightly less than one repetition of the waveform. Set
the holdoff to this time to generate a unique trigger point for a repetitive waveform. Only
edge trigger and serial trigger have holdoff option. The holdoff time of the oscilloscope is
adjustable from 100ns to 1.5s.
1. Press the Stop button, and then use the Horizontal Position Knob and the
Horizontal Scale Knob to find where the waveform repeats. Measure this time using
cursors; then, set the holdoff.
2. Press the Setup button on the front panel to enter the TRIGGER function menu. The
default trigger type is edge.
3. Press the Holdoff Close softkey; and then turn the Universal Knob to set the desired
holdoff time.